Cryptographic architecture for secure, private biometric identification

ABSTRACT

A semiconductor device for securely controlling access to a cryptographic processor including a semiconductor package with a biometric data capture device therein operative to acquire data associated with predetermined biometric characteristic of a user and store it as a biometric key, and a processing unit in the package coupled to the data capture device. An encryption/decryption circuit is also disposed in the semiconductor package and is operative to perform encryption or decryption on input data utilizing the biometric key.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The apparatus and methods consistent with the present invention relatesto mobile computers for use in wireless local area networks, and moreparticularly to the security network architecture, configurationsoftware and communications protocols needed to support the biometricidentification of an authorized user of a mobile unit to be operated insuch networks, and from one secure network to another secure network.

2. Glossary of Terms

Access Agent: A logical component that provides support for differentaccess protocols and streams—Frame Relay, HDLC (High Data link Control)CBO (Continuous bit Operations, ATM (Asynchronous Transfer Mode), orTCP/IP.

Call (noun): Point-to point multimedia communication between two IPnetwork endpoints. The call begins with the call setup procedure andends with the call termination procedure. The call consists of thecollection of reliable and unreliable channels between, all the channelsterminate at the Gateway where they are converted to the appropriaterepresentation for the PSTN end system.

Caller: The entity initiating a call.

Called: The destination of a call

Dynamic Address Mapping Service: A service which provides a lookupfunction between text based strings and IP addresses and/or phonenumbers, where the result of the lookup can change relatively quicklyover time.

Endpoint: An H.323 Terminal or Gateway. An endpoint can call and becalled. It generates and/or terminates information streams.

Gatekeeper: The Gatekeeper (GK) is an H.323 entity that provides addresstranslation and controls access to the network for H.323 Terminals andGateways. The Gatekeeper may also provide other services to the H.323Terminal and gateways, such as bandwidth management and locatingGateways.

Gateway: An H.323 Gateway (GW) is an endpoint which provides forreal-time, two way communications between H.323 Terminal on a IP networkand: other ITU terminals; phones on the PSTN; other terminals on othernetworks.

H.323 Entity: Any H.323 component, including H.323 Terminals, Gateways,Gatekeepers.

IMTC: (International Multimedia Teleconferencing Consortium) Anorganization whose mission is to bring together all organizationsinvolved in the development of interactive, multimedia teleconferencingproducts and services to help create and promote the adoption ofindustry-wide interoperability standards. The VoIP forum is part of theIMTC.

Information Stream: A flow of information of a specific media type (e.g.audio) from a single source to one or more destinations.

Internet address: The network layer address of an H.323 endpoint,Gatekeeper, or DNS server.

Internet: An inter-network of networks interconnected by bridges orrouters. LANS described in H.323 may be considered parts of suchinternetworks.

IP network: A network that uses IP as the network layer protocol. Thisincludes networks such as Internet, Intranets, LANs etc.

RAS Channels: Unreliable channels used to convey the registration,admissions, bandwidth change, and status messages (following H.225.0)between H.323 entities.

Reliable Channel: A transport connection used for reliable transmissionof an information stream from its source to one or more destinations.

Reliable Transmission: Transmission of messages from a sender to areceiver using connection-mode data transmission. The transmissionservice guarantees sequenced, error-free, flow-controlled transmissionof messages to the receiver for the duration of the transportconnection.

Transport Connection: An association established by a transport layerbetween two H.323 entities for the transport of data. In the context ofH.323, a transport connection provides reliable transmission ofinformation.

VoIP: Voice over Internet Protocol. The VoIP Forum is developer ofspecification of such protocol.

Zone: A zone, as defined in H.323, is a collection of all terminals,Gateways (GW), and Multipoint Control Units (MCU) managed by a singleGatekeeper (GK).

3. Background of the Invention

a. Communications Networks

A typical data communications network system comprises at least oneserver and two or more clients interconnected through a network link.The International Standards Organization (ISO) has publishedspecifications for their Open Systems Interconnection (OSI) referencemodel for layered data communications, which has become a standardframework for describing network communications systems. The ISOreference model is divided into seven layers, each defining a set ofservices and related protocols for handling messages at that layer. TheISO's reference model defines the following seven layers; (1) physical;(2) data link; (3) network; (4) transport; (5) session; (6)presentation; and (7) application. Since the concepts and teachings ofthe present invention generally fall within the transport throughapplication layers; a detailed discussion of the operations taking placeat the lowermost (e.g., physical, data link, and network) layers was notnecessary for purposes of describing the present invention, as theoperations at these levels are known to those skilled in the art and aretransparent to the operations of the present invention.

The physical layer comprises the actual physical devices and medium usedto transmit information. The data link layer frames data packets andcontrols physical layer data flow, insuring delivery of data regardlessof the actual physical medium. The network layer addresses and routesdata packets. It creates and maintains a route in the network between asource node and a destination node. The transport layer creates atransport pipeline between nodes and manages the network layerconnections. The session layer typically provides remote procedure call(RPC) support, maintains the integrity of the connection between nodes,and controls data exchange. The presentation layer encodes and decodesdata and provides transparency between nodes. Finally, the applicationlayer provides the interface to end-user processes and providesstandardized services to applications.

b. Wireless LANs

Wireless local area networks use infrared or radio frequencycommunications channels to communicate between portable or mobilecomputer terminals and stationary access points or base stations. Theseaccess points are in turn connected by a wired (or possibly wireless)communication channel to a network infrastructure which connects groupsof access points together to form a local area network, including,optionally, one or more servers or host computer systems.

Wireless and radio frequency (RF) protocols are known which support thelogical interconnection of portable roaming terminals having a varietyof types of communication capabilities to host computers. The logicalinterconnections are based upon an infrastructure in which at least someof the remote terminals are capable of communicating with at least twoof the access points when located within a predetermined rangetherefrom, each terminal unit being normally associated with and incommunication with a single one of such access points. Based on theoverall spatial layout, response time, and loading requirements of thenetwork, different networking schemes and communication protocols havebeen designed so as to most efficiently regulate the communicationsbetween a given terminal and the network through the selected accesspoint. One such protocol is described in U.S. Pat. Nos. 5,029,183;5,142,550; 5,280,498; and 5,668,803, each assigned to SymbolTechnologies, Inc. and incorporated herein by reference.

Another such protocol is described in U.S. Pat. No. 5,673,031. Stillanother protocol is set forth in the ISO/IEC 8802-11, or ANSI/IEEE Std802.11 entitled “Wireless LAN Medium Access Control (MAC) and PhysicalLayer (PHY) Specifications” (1999 edition) available from the IEEEStandards Department, Piscataway, N.J. (hereinafter the “IEEE 802.11Standard”).

The IEEE Project 802 is concerned with network architecture for localarea networks. The IEEE 802.11 Standard is directed to wireless localarea networks, and in particular specifies the MAC or the data linklayer and the PHY or physical link layer.

In Europe, the European Telecommunications Standards Institute (ETSI)has been working on HIPERLAN (European High PERformance LAN), the nextgeneration of high speed wireless systems. The frequency spectrum forHIPERLAN in the 5 GHz and 17 GHz bands has been allocated by theEuropean Conference of Postal and Telecommunications Administrations(CEPT), with a data rate of over 20 Mbit/sec.

c. Modulation Techniques

The current implementations of commercial wireless LAN networks utilizea radio operating in the 2.4 to 2.4835 GHz spread spectrum band which isthe industrial, scientific, and medical (ISM) band allocated forunlicensed use by the FCC. The current systems utilize one of two basictypes of spread spectrum modulation: direct-sequence andfrequency-hopping, or a technique known as complementary code keying(CCK).

d. Roaming

The term “roaming” relates to mobile units associating with differentaccess points. Each mobile unit analyzes received signals from accesspoints to identify and associate with an eligible access point.Analogous to cells in a cellular telephone network, the region around agiven access point may also be referred to as a “cell.” Roaming betweencells provides great flexibility and is particularly advantageous inlocations that are difficult to wire, for simple relocation of workstations, and for portable work stations.

Although the IEEE 802.11 Standard provides the basic packet types whichenable roaming, it does not actually set the roaming algorithm.According to the standard, the mobile unit determines the access pointwith which it will associate and the access point must accept the mobileunit unless the access point is defective or certain alarm conditionsexist, such as memory full. There is, however, no suggestion of how, orby what criteria, other than those mentioned above, the mobile unitmight select an appropriate access point, or an optimum access point.

In order for a mobile unit to associate with an access unit the mobileunit follows an association protocol. The mobile unit firstly sends outa probe packet having no destination address which is accordinglyaccepted by all access units within range. The probe packet contains anidentifying address for the mobile unit has sent it. The access unitthen transmits a probe response packet which includes information suchas the access unit address, the hopping pattern, the present channel,time left in the present channel and other timing information. Themobile unit then decides whether or not to associate with a given accessunit, based on for example the strength of the signal of the access unitand any information the access unit may have issued indicating how manymobile units are already associated with it. If the mobile unit decidesto associate, it sends an associate message or packet and the accessunit decides whether to accept the association request and issues anassociation response after the request is accepted.

In addition the access unit transmits a “beacon” at predeterminedintervals containing, in addition to other information, timinginformation similar to that contained in probe response packet.

The mobile units can operate in two power management modes, eithercontinuously awake mode (CAM) or power save polling (PSP) mode. In theformer mode, CAM, the mobile unit remains in substantially continuouscommunication with an access unit so as to receive and transmit allinformation intended for the mobile unit practically instantaneously. Ofcourse that mode of operation requires a high level of power consumptionwhich is not always desirable for a portable mobile unit which isrelying on internal power such as batteries. In the alternative PSPmode, the mobile unit sends out a polling signal at predeterminedintervals of time to enquire whether an associated access unit hasstored any messages for that mobile unit in a suitable buffer. Similarlythe mobile unit can store any message to be transmitted in a buffer andtransmit all of the messages so stored at predetermined intervals. Sucha mode of operation clearly allows decreased power consumption. Underthe IEEE 802.11 protocol the beacon signal contains information aboutwhich PSP stations have data waiting.

e. Coordination Functions

In the IEEE 802.11 network architecture, the management of stationswithin a region in which the station can communicate with each other isperformed by software known generically as a Coordination Function (CF).A group of mobile units that can communicate with one another is knownas a basic service set or BSS. In order to ensure that communicationsare coordinated, the CF determines when a station operating within a BSSis permitted to transmit and may be able to receive protocol data units(PDUs) via the wireless medium. The BSS is formally defined as the setof stations controlled by a single Coordination Function. There are twotypes of coordination functions—the Distributed Coordination Function(DCF), and the Point Coordination Function (PCF). The use of DCF ismandatory, while PCF is optional under the IEEE 802.11-1999 standard.

A larger group of network units, called the extended service set or ESSis defined as a set of one or more interconnected Basic Service Sets andintegrated LANS which appear as a single BSS to the logical link control(LLC) layer at any station associated with one of those BSSs.

The key concept is that the ESS network appears the same to an LLC layeras an independent BSS network. Stations anywhere within an ESS maycommunicate with each other and mobile stations may move from one BSS toanother (within the same ESS) transparently to LLC. Mobile unitscommunicate with an AP, and the AP forwards to traffic among themselvesto the destination BSS, thus facilitating the roaming of mobile unitsfrom one BSS to another.

One (or more) independent BSS or ESS networks may be physically presentin the same space as one or more ESS networks. For example, an ad hocnetwork may be operated in the region of an ESS network; or physicallyoverlapping independent IEEE 802.11 networks may be set up by differentadjacently located organizations, each with their own ESS identificationcode.

f. Security

IEEE 802.11 specifies an optional privacy algorithm, WEP that isdesigned to satisfy the goal of wired LAN “equivalent” privacy. Thealgorithm is not designed for ultimate security but rather to be “atleast as secure as a wire.” IEEE 802.11 uses the WEP mechanism toperform the actual encryption of messages. Privacy may only be invokedfor data frames and some Authentication Management frames. All stationsinitially start “in the clear” in order to set up the authentication.

SUMMARY OF THE INVENTION

Briefly, and in general terms, the present invention provides asemiconductor device for securely controlling access to cryptographicprocessor including a semiconductor package; a cryptographic processorin the semiconductor package, including a biometric data capture circuitwhich acquires data associated with predetermined biometriccharacteristic of a user and stores it as a biometric key; and aencryption/decryption circuit and operative to perform encryption ordecryption on input data utilizing the biometric key.

Another feature of the present invention is to provide a mobile computerhaving a hand-held housing and a wireless RF transceiver in the housingto transmit and receive data over a wireless communications channel. Adata input device and a data output device is also provided in thehousing. A cryptographic processor is disposed in a single semiconductorpackage in the housing, including a biometric data capture devicecontained in the semiconductor package to capture data associated withpredetermined biometric characteristic of a user and store it as abiometric key, and a encryption/decryption circuit operative to performencryption or decryption on input data utilizing the biometric key.

Still another feature of the present invention is to provide a securewireless local area network including a mobile computer including acryptographic processor and a wireless RF transceiver and an accesspoint connected to a wired local area network including a wireless RFtransceiver capable of communication with the mobile computer.

A security protocol program is executed in the cryptographic processorin the mobile computer and in the access point to establishauthentication of the mobile computer by verification of a storedencrypted biometric key in the cryptographic processor.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a block diagram of the architecture of a mobile computerincorporating the present invention;

FIG. 2 is a flow chart of the method of the present invention;

FIG. 3 is a block diagram of a secure network using the presentinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Today's authentication and access control techniques rely on sharedsecrets such as passwords and/or physical tokens. Tokens are easily lostor stolen. Passwords are cumbersome so in many instances actions aretaken which compromise their security, e.g.; using a common password formultiple applications, writing down passwords in day planners ornotebooks, using non-secure character strings such as names or birthdates.

Passwords and tokens do not represent true end-to-end authentication,that is, human-to-machine. True authentication requires a physiologicalbiometric of the person. But biometrics that uniquely identifies aperson is an extremely sensitive and personal piece of information andmust be securely managed (protected) within a computing environment. Theproblem is how to alleviate concerns of “identity theft” and biometricmisuse.

The threat of compromise is magnified by trends in open platform mobilecomputing. Open platform mobile devices are expected to run scripts andexecutable programs loaded from external sources (e.g. loaded via emailor web browsing). Such malicious “programs” (e.g. through a “Trojanhorse”) can compromise the integrity of non-secured data stored inmemory or accessible elsewhere by the processor.

The privacy of biometric data is also more readily compromised by newmodalities of transport. Today data is often transported over cables inphysically secured environments, administered by a single authority. Thenew paradigm is to use public networks for transport which are neithercentrally administered nor physically secured. Wireless media compoundsthe problem by virtually eliminating physical security.

There are numerous methods of biometric identification such as retinalor iris scans, facial features, voiceprints, fingerprints, handgeometry. All biometric systems start with elements that can acquire thenecessary information in a computer useable form. For voice this is amicrophone, a set of amplifiers and an analog to digital converter(sometimes referred to as a CODEC). For facial feature ID the sensor maybe an imager taking the form of optical lenses and a sensing device(e.g. CCD or CMOS array). The sensor may also be a sensor for detectinga fingerprint. In all cases the biometric data output of the sensor mustbe secured.

Since the processor can be compromised by a malicious program, thesensor data must be secured independently of the main CPU. Therefore,taking the data into memory and then encrypting it for transport (orfuture processing) is not sufficient.

The proposed solution according to the present invention is to considerthe biometric data and/or sensor a component of the securityarchitecture. FIG. 1 illustrates a block diagram of a mobile computerwith a biometric sensor 11 reading and transporting data to a cryptomodule 10. The sensor 11 can either be a separate component orintegrated into the crypto module 10. Thus, it may be a CCD device forimaging a face or fingerprint, such device being part of the module 10.

The mobile computer itself is illustrated by a highly simplified blockdiagram depicting a microprocessor 15, non-volatile memory 16, volatilememory 17, network interface or connect unit 18, and input/outputdevices 22, which are all interconnected by a bus 14. The crypto module10 is also connected to the bus 14. The biometric sensor data isencrypted prior to entering the processor domain or bus 14. That is, theprocessor 15 cannot access the unencrypted biometric data nor can itaccess the key used to encrypt the data. Thus, the sensor 11 registersthe actual biometric data, and processes and stores in the module 10.All key creation, key exchange, and authentication is done autonomouslybetween the crypto module 10 and an end server or system thatadministers biometric keys or prints.

All biometric and cryptographic keys are stored securely in a store 12in the crypto module 10. The module is tamper-proof to thwart a physicalattack by an invasive intruder. Once the secure biometric data is storedin memory 12, it can be transmitted to a remote server for verification.It is envisioned that the cryptographic module will use standards basedend-to-end security protocols such as IPSec.

In a similar manner, the cryptographic module can be used to performclient based verification. In this mode, known biometric prints (shownas reference blocks 19 and 20) are either retrieved and/or stored inencrypted fashion in memory 17. The encrypted prints can be loaded intothe crypto module 10. The crypto module 10 decrypts the data andperforms an internal biometric verification 13. Once again, theverification is performed in a secure, autonomous domain in that ofmodule 10. Once a user has been verified by the local mobile computer, asecondary authentication process from the mobile computer to a remoteserver can take place over the network 21, as will be subsequentlyexemplified.

Turning next to FIG. 2, there is shown a sequence of operations forinitializing the cryptographic module, and utilizing it in actual dataprocessing environment. At the first block 200, the user entersbiometric data directly into the crypto module using the sensor 11. Inan embodiment, the biometric data is then encrypted, using a definedalgorithm and key. The biometric data is then stored in memory in themodule, as shown at block 201. The module 10 is then ready to processdata. As a cryptographic device, its function is to receive as inputencrypted data and return as output the decrypted or actual data. Themodule thus receives encrypted data input using the biometric key as anencryption parameter, 202. Data which is not encrypted using thebiometric key may be processed elsewhere in the computer, or if the keyis provided to the module 10, by using the module for decryption.Assuming a biometric key is used, the module decrypts the data inputusing the stored biometric key, as shown at block 203 typically at thepresentation layer level. Finally, the decrypted data is output from themodule, as shown at block 204.

FIG. 3 is a block diagram of a secure network architecture using thepresent invention. The mobile computer 300 is illustrated as being incommunication with an access point 302. The association and roamingproperties of a mobile computer in an IEEE 802.11 wireless network havebeen described above, and need not be repeated here. In the context ofan IP network using VoIP, which is one of the areas of application ofthe present invention, the access point 302 may also serve as an H.323Gatekeeper or Gateway. The mobile computer 300 may roam from accesspoint to access point in the WLAN, and even from one ESS to another ESS.Although WEP may be used, at the radio frequency MAC level, enhancedsecurity requires software protocols above the MAC level. The use of auser biometric 301 is a key feature according to the present inventionfor providing this enhanced security.

The network architecture entails the use of an access agent and/or anauthentication agent. The key feature is the use of upper layerauthentication protocols, and may be concerned with key distribution,mutual authentication of endpoint, H.323 entities, and stations ormobile units, below the presentation layer processing described above.

The protocols may also define a secure network zone in which privacy,data authentication, and replay protection are, in some sense, assured.The use of RAS channels through such zones may also be possible. Thus,the frame types that may be exchanged between different stations may begrouped into different security classes, corresponding to differentstation states and zones, but such discussion goes beyond the scope ofthe present invention.

The access point is connected to a network 303 which includes anauthentication server 304. Although network 303 may be secure, it willbe connected through routers 305 to another possibly insecure, network306 on which the source client 307 is located. An authentication server308 may be provided on that network if end-to-end authentication isrequired. The source client 307 sends encrypted data (using thebiometric key) through network 306, routers 305, to network 303 andaccess point 302 to the mobile computer 300, where it is decrypted. Thecrypto module in the mobile computer operates as previously described,defined a security architecture from the WEP MAC level, through 802.1Xports, and authentication agents, using the information streamencryption/decryption processor using a biometric key securely stored inthe crypto module.

Various aspects of the techniques and apparatus of the cryptographicmodule may be implemented in digital circuitry, or in computer hardware,firmware, software, or in combinations of them. Apparatus of theinvention may be implemented in computer products tangibly embodied in amachine-readable storage device for execution by a programmableprocessor, or on software located at a network node or website which maybe downloaded to the computer product automatically or on demand. Theforegoing techniques may be performed, for example, single centralprocessor, a multiprocessor, one or more digital signal processors, gatearrays of logic gates, or hardwired logic circuits for executing asequence of signals or program of instructions to perform functions ofthe invention by operating on input data and generating output. Themethods may advantageously be implemented in one or more computerprograms that are executable on a programmable system including at leastone programmable processor coupled to receive data and instructionsfrom, and to transmit data and instructions to, a data storage system,at least one input device, and at least one output device. Each computerprogram may be implemented in a high-level procedural or object-orientedprogramming language, or in assembly or machine language if desired; andin any case, the language may be compiled or interpreted language.Suitable processors include, by way of example, both general and specialpurpose microprocessors. Generally, a processor will receiveinstructions and data from read-only memory and/or random access memory.Storage devices suitable for tangibly embodying computer programinstructions and data include all forms of non-volatile memory,including by way of example, semiconductor devices, such as EPROM,EEPROM, and flash memory devices; magnetic disks such as internal harddisks and removable disks; magneto-optical disks; and CD-ROM disks. Anyof the foregoing may be supplemented by or incorporated in, speciallydesigned application-specific integrated circuits (ASICs).

It will be understood that each of the elements described above, or twoor more together, also may find a useful application in other types ofconstructions differing from the types described above.

While the invention has been illustrated and described as embodied in acryptographic architecture, it is not intended to be limited to thedetails shown, since various modifications and structural changes may bemade without departing in any way from the spirit of the presentinvention.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can, by applying current knowledge,readily adapt it for various applications without omitting featuresthat, from the standpoint of prior art, fairly constitute essentialcharacteristics of the generic or specific aspects of this inventionand, therefore, such adaptations should and are intended to becomprehended within the meaning and range of equivalence of thefollowing claims.

1. A semiconductor device for securely controlling access to cryptographic processing of data comprising: a semiconductor package; a cryptographic processor disposed in the semiconductor package, the processor including a biometric data capture device operative to acquire biometric data associated with a predetermined biometric characteristic of a user and store the biometric data as a biometric key, and an encryption/decryption circuit operative to perform encryption or decryption on input data utilizing said biometric key.
 2. A device as defined in claim 1, wherein the stored biometric key is encrypted data.
 3. A device as defined in claim 1, wherein the biometric data capture device performs an encryption operation on the biometric data to produce encrypted source data.
 4. A device as defined in claim 3, wherein the processor compares the encrypted source data with the stored biometric key.
 5. A device as defined in claim 3, wherein the predetermined biometric characteristic is a fingerprint.
 6. A mobile computers, comprising: a hand-held housing; a wireless RF transceiver in the housing to transmit and receive data over a wireless communication channel; a data input device in the housing; a data output device in the housing; and a cryptographic processor disposed in a single semiconductor package, the processor including a biometric data capture device contained in the semiconductor package to capture biometric data associated with a predetermined biometric characteristic of a user and store the biometric data as a biometric key; and an encryption/decryption circuit disposed in the semiconductor package operative to perform encryption or decryption on input data utilizing said biometric key.
 7. A device as defined in claim 6, wherein the stored biometric key is stored as encrypted data.
 8. A device as defined in claim 6, wherein the biometric data capture device performs an encryption operation on the biometric data to produce an encrypted key.
 9. A device as defined in claim 8, wherein the processor utilizes the stored biometric key with a cryptographic algorithm.
 10. A device as defined in claim 8, wherein the predetermined biometric characteristic is a fingerprint.
 11. A secure wireless local area network comprising: a mobile computer including a cryptographic processor and a wireless RF transceiver; an access point connected to a wired local area network, the access point including a wireless RF transceiver capable of communication with the mobile computer; and a security protocol program executed in the cryptographic processor in said mobile computer and in said access point to establish authentication of the mobile computer by said access point by verification of a stored encrypted biometric key in said cryptographic processor.
 12. A network as defined in claim 11, wherein said cryptographic processor includes a biometric data capture device and an encryption/decryption circuit operative to perform encryption or decryption on input data to the processor utilizing said biometric key.
 13. A network as defined in claim 12, wherein the stored biometric key is encrypted biometric data from an authorized user of the network.
 14. A network as defined in claim 13, wherein the processor performs an encryption operation on the biometric data to produce encrypted source biometric data which is stored as the biometric key.
 15. A network as defined in claim 14, wherein the processor compares the encrypted source biometric data with the biometric data of a current user of the mobile computer as derived by the biometric data capture device.
 16. A network as defined in claim 14, wherein the biometric data is a fingerprint.
 17. A network as defined in claim 14, further comprising an authentication server connected to the wired local area network.
 18. A network as defined in claim 17, further comprising a software protocol above a radio frequency MAC level. 